Floor surfacing machine



May 8,. 1934. P. VINELLA FLOOR SURFACING MACHINE Filed Jan. 2, 1932 5Sheets-Sheet 1 x 1 4 3 1 n H W 4 wk 1m gwva'nkw Pele?" Vin/elm May 8,1934. PI VINELLA 1,958,977

FLOOR SURFAC ING MACHINE Filed Jan. 2, 1932 3 Sheets-Sheet 2 May 8,1934.

P VINELLA 1,958,077

FLOOR SURFACING MACHINE Fiied Jan. 2. 1952 3 Sheets-Sheet '3 gwuento'cPeier Wine ZZa/ Patented May 8, 1934 ATENT" OFFICE Application January2,

2 Claims.

The present invention relates to a terrazzo floor grinding mechanism.

In the grinding of terrazzo floors it sometimes happens that a pipe orother object is imbedded in the flooring material and projects upwardlytherefrom. If the rotating grinding heads of a terrazzo floor grindingmechanism are inadvertently moved so as to strike such an object, itusually causes a breakage of some portion of the machine, usuallystripping of the driving gear between the motor and the grinding head.

An object of the present invention is to make an improved and simplifiedterrazzo floor grinding mechanism.

In order to attain this object, there is provided, in accordance withone feature of the invention, a motor mounted upon a supporting frameand connected by means of a friction clutch to a grinding head drivinggear encased in a gear housing formed integrally with a supportingframe. This grinding head driving gear is in meshed engagement with asecond grinding head driving gear, also encased in said gear housing. Alaterally tilting wheeled carriage is secured to the frame and held inposition by means of springs in accordance with one embodiment of theinvention, while a modified form of the invention comprises a rigidcarriage with a wheel axle resiliently supported therein and providedwith adjusting means by means of which the tension on the wheels may becontrolled.

These and other features of the invention will be morefully brought outin the following description and the accompanying drawings, wherein: 1

Figure 1 is a longitudinal sectional view through a mechanism embodyingthe invention, the line of section being indicated by the line 11 onFigure 3, the upper portion of a driving motor and of a handle beingbroken away.

Figure 2 is a transverse vertical sectional view on the line 22 ofFigure 3, the upper portion of the motor being broken away.

Figure 3 is a top view of the device with the motor removed and aportion of a frame plate broken away to show the gear arrangement.

Figure 4 is a View in front elevation of a modified form of a carriage.

Figure 5 is an enlarged end view of the carriage shown in Figure 4 withthe wheels and axles removed therefrom.

Figure 6 is a sectional view on the line 6-6 of Figure 5, showing theaxle in place.

Figure 7 is a view in rear elevation of a preferred form of supportingcarriage.

1932,; Serial No. 584,408

Figure 8 is a top view of the carriage shown Figure 7 Figure 9 is a topview of a driving spider for a grinding head.

Figure 10 is a side view of the spider shown in Figure 9.

Figure 11 is a top view of a grinding head.

Figure 12 is a lower view of one of the arms of the grinding head shownin Figure 11.

Figure 13 is a side view of the arm shown in Figure 12.

Figure 14 is a side view of the spider shown in Figure 11; and

Figure 15 is a sectional View on the line 15-15 of the arm shown inFigure 12 as it would appear with a grinding stone inposition therein.

Referring to the drawings in detail, a plate 1, preferably of castmetal, has a rim 2 cast integrally therewith around the sides and rearend thereof to act as a reinforcement and to serve as a tool holder forthe tools necessary in operating the machine. Four motor support bosses3 are cast integrally with this plate to extend upwardly therefrom andupon the bosses are bolted legs 4 which support a driving motor 5. Theshaft 6 of the driving motor has keyed thereto, as by means of aWoodruff key 7, a disk 8 having a downwardly projecting flange aroundthe periphery thereof.- An annular member 9 of the same diameter as thedisk 8 is bolted thereto by means of bolts 10 around the periphcry ofthese members. A clutch facing disk 11 of suitable material such as thatused in brake linings and a second member 12, of similar material, aremounted, one above and one below a clutch disk member 13, so as tofrictionally grip the clutch disk member and cause it to normally rotatewith the member 8 and the member 9. The lower end of the motor shaft 6is mounted in a recess in the upper portion of the member 13 so as to berotatable therein, although it is apparent that normally the shaft 6will rotate the member 13, due to the frictional engagement of theclutch plate 13 by the members Sand 9. Formed integrally with the clutchplate 13 is a pinion 14, the lower end of which is rotatably mounted ina ball bearing 15. The pinion 14. is in driving engagement with agrinding head drive gear 16, which is mounted upon a shaft 1'7 which isrotatably mounted on roller bearings 18 and 19. The upper roller bearing19 is mounted in a cup-shaped depression formed by an annular ridge 20on the top of the upper plate 1, and a nut 21 is threaded onto the upperend of the shaft 17 to hold the roller bearing in position. A cap 22 ismounted on the annular ridge 20 and covers the upper end of the shaft 17to protect it from dust. This cap is held in position by means of screws23. A gear housing member 24, preferably of cast metal, is secured tothe lower face of the front portion of the frame plate 1 and is boltedthereto as by means of bolts 25. A gasket, not shown, which may be ofpaper or other suitable material, provides a grease-tight seal betweenthe frame plate 1 and the gear housing member 24. A pair of annularrecesses 26 are provided in the lower face of the gear housing 24, andin these are mounted roller bearings in which the shafts 17 arerotatably mounted. A three-armed spider 28, shown in detail in Figures 9and 10, is keyed to the lower end of the shaft 17 and is held inposition thereon by means of a nut 29. The arms of the spider 28 areconnected as by means of screws 30 to a flexible disk 31 to the lowersurface of which is connected, as by means of cap screws 32, a grindinghead 33. This construction provides a flexible driving connectionbetween the spider 28 and the grinding head 33. The lower end of theshaft 17 is provided with a recess lined with bearing metal 34 and theupper portion of a raised central portion 35 of the grinding head isalso provided with a cupshaped recess in which is mounted a bearing ball36 which seats in the recess in the lower end of the shaft 17. Thisprovides a universal connection between the shaft 17 and the grindinghead 33 with the ball connection taking the thrust to which the joint issubject in use. Each of the arms 37 of the grinding head is providedwith downwardly projecting portions 38, 39, 40, and 41 (see Figure 12),which are positioned to receive a grinding stone 42 therein, thegrinding stone being securely locked in position as by means of a woodenwedge 43 driven between the member 41 and the grinding stone 42.

A wheel support for the rear of the machine frame member 45, preferablyof cast metal, having downwardly sloping and tapering side portions 46,with a transversely positioned vertical reinforcing rib 47 formedintegrally therewith. A forwardly projecting portion 48 is provided witha transverse opening 49 therethrough. This opening is tapered outwardlyboth ways from its center so as to permit a limited lateral tilting ofthe carriage with respect to a pin 50 (see Figure 1). The forwardlyprojecting portion 48 is mounted between a pair of lugs 51 and a shaft52 of a diameter equal to the smallest diameter of the opening 49 andsecures the portion 48 in position between these lugs. The member 48 isconstructed to have a loose fit between the lugs 51 so as to permit alimited amount of lateral tilting movement between the frame 1 and themember 45. A portion 53 projects rearwardly from the member 45 and isprovided with curved side portions 54. This rearwardly projectingportion is mounted to be free for vertical slidable movement in aslotted opening 57 in a downwardly projecting portion 55 of the framemember 1. A bolt 56 having threaded engagement with the frame member 1extends downwardly into the upper end of the slotted opening 57 to limitthe upward movement of the portion 53 therein. A locknut 58 is threadedonto the bolt 56 to secure the bolt in adjusted position. A pair ofannular recesses 59 are provided, one on each side of the member 45 toreceive coil springs 60 therein. A pin 61 is mounted in the center ofeach of the recesses 59 and extends upwardly through slotted openings inthe plate 1. The coil springs so rest against the lower surface of theplate 1 and tend to keep the plate 1 normally level. When an unevenportion of floor is encountered during a grinding operation, the springspermit a limited lateral tilting of the frame with respect to thewheels, so that the grinding heads remain in alinement with the floorsurface.

A modified form of carriage is shown in Figures 4, 5, and 6. In thisconstruction a frame 61 has a transverse upper portion 63 which isfirmly bolted to the lower surface of the plate 1, as by means of bolts62. From each outer end of the transverse portion 63 are a pair ofdownwardly projecting arms 64 and 65 in parallel, spaced relation. Aslidable block 66 is mounted between each of these pairs of arms, eachof these blocks being provided with an opening 6'7 in which an axle 68is mounted. A slidable plate 69 is swiveled to a bolt '70 threadedthrough each end of the member 63 between the arms 64 and 65. A coilspring '71 is mounted to be held in compression between each of theplates 69 and the blocks 66 to resiliently position the axle 68.

I claim:

1. A floor grinding mechanism having a frame, a pair of oppositelyrotatable grinding heads mounted thereon, power drive means mounted onsaid frame and operatively associated with said grinding heads to rotatesaid heads in opposite directions upon energization of said drive means,a laterally tiltable and vertically adjustable wheeled carriage mountedto partially support said power drive means, and resilient means mountedbetween said carriage and said frame to normally hold said frame inlateral alinement with the base of said wheeled carriage.

2. In a terrazzo floor grinder having a frame, a pair of oppositelyrotatable grinding heads carried thereby, and power drive meansoperatively connected to said grinding heads; a wheeled supportingstructure comprising a transversely disposed pivot member, a wheelsupport member pivotally mounted thereon with freedom for limitedlateral tilting movement, a vertically slotted opening positionedrearwardly from said pivot member, a projection carried by said Wheelsupport member positioned to ride in said slotted opening, adjustingmeans mounted to limit the movement of said projection in said slot,spring means mounted to resiliently maintain said wheel support memberin a laterally equalized position with respect to said frame, and a pairof wheels rotatably mounted, one on each side of said wheel supportmember.

PETER VINELLA.

